Synchronous digital systems rely on one or more clock signals to synchronize elements across the system. Conventionally, one or more clock signals are distributed across the system on one or more clock lines. Data within the system may be generated based on each clock. However, due to various reasons including initial state of logic gates, clock buffer delays, high capacitance of heavily loaded clock lines and propagation delays, the edges of a clock signal in different parts of the system may not be adequately synchronized making it difficult to generate synchronous data, particularly phase-aligned data. When edge alignment of each clock is achieved, the data is synchronous and phase aligned.
Some conventional techniques for generating synchronous data use phase-locked loops (PLLs) that rely on a voltage-controlled oscillator (VCO). The use of such PLLs may result in unacceptable jitter and poor noise performance due the operation of the VCO. Some other conventional techniques for generating synchronous data use a master-slave approach in which slave devices are synchronized with a single master device. The use of a single master device can be a single point of failure reducing system reliability.
Thus, there are general needs for improved systems and methods for generating synchronous data, including phase-aligned data. There are also general needs for systems and methods for generating phase-aligned data with improved jitter and phase-noise performance. There are also general needs for systems and methods for generating phase-aligned data that do not rely on a single master device.